Perfluoropolyethers (PFPE) polymers comprising amino groups at their chain ends (hereinafter “PFPE-amino”) are potentially interesting materials from the industrial perspective.
PFPE-amino and methods for their production are known in the art. For example U.S. Pat. No. 6,083,600 (INTERNATIONAL BUSINESS MACHINES CORPORATION) discloses PFPE wherein the polymer backbone is terminated with at least one amine end group, which is linked to the polymer backbone through a methylene bridging group. U.S. Pat. No. 6,984,759 (SOLVAY SOLEXIS S.P.A.) discloses a method for the preparation of PFPE comprising primary amino groups at its chain ends, wherein the amino groups are linked to the PFPE chain through a methylene bridging group.
However, when amino groups are directly linked to the PFPE chain, said amino groups have poor basic properties. As a consequence, the resulting PFPE-amino derivatives are poorly reactive and of little use both as intermediates for the synthesis of polymers and as additives, for example in coating compositions.
Also, the synthesis known in the art are not convenient on industrial scale, as they require several steps of chain ends modification under tricky and expensive reaction conditions.
WO 2013/092632 (SOLVAY SPECIALTY POLYMERS ITALY S.P.A) discloses (per)fluoropolyether compounds having two chain ends, wherein one or both chain ends is a —CF2-group covalently bound to an optionally substituted aromatic or heteroaromatic group through a -carbon-carbon-bond.
EP 0249048 (AUSIMONT S.P.A.) discloses cross-linking of epoxy resins by means of polyfunctional perfluoropolyethers containing groups which are reactive with the epoxy groups and/or with the hydroxy groups present in the starting resin.